In a retrospective study of 185 patients with transitional cell carcinoma of the renal pelvis and ureter, of whom 127 were treated by total nephroureterectomy and 58 by conservative resection, the survival of those with superficial well differentiated tumours was greater than 90% in each group. When urothelium was left behind after conservative resection, there was a 22% rate of recurrence on the same side but this almost only occurred when the original tumour had been multifocal. Post-operative radiotherapy did not improve survival.